Current Mode Control of Fuel Cell Fed Interleaved Boost Converter for Ripple Current Minimization

Fuel cells normally supply high current at low voltage. Hence they need to be integrated with boost converters to supply load at elevated voltages. Boosting of voltage at the load level amplifies the effect of ripple in load current at the input side. The life time of fuel cell catalyst reduces with the increase in current ripple. This paper proposes an effective solution to reduce the ripple with the use of interleaved boost converters and non-linear carrier based current mode control. Performance of the controller has been tested in simulation and validated through experimentation on a 1.2kW fuel cell stack for wide variations in load and fuel flow conditions. It is observed that, compared to other control techniques, the proposed controller has better dynamic response and it does not need any complex multiplier or divider circuit for its implementation. A prototype rated 1.2 KW has been built and tested.